1. Field of the Invention
The present invention relates generally to a liquid crystal display (LCD) module, and more particularly to a direct-light illuminating unit for the LCD module, which has light shade to shade the lamps at where has a greater luminance.
2. Description of the Related Art
Liquid crystal displays (LCDs) have been applied to computer monitors, video devices, consumer electronics and the like. A conventional LCD module is mainly composed of a liquid crystal panel and an illuminating backlight unit. The backlight unit provides illumination to the liquid crystal panel so that the panel can show predetermined images.
FIG. 1 shows a conventional direct-light illuminating unit 100 having a frame 102 on which three U-shaped lamps 106 and a diffuser plate 106 are mounted. Each lamp 104 has two straight portions 108 and a connection portion 110 connected to ends of the straight portions 108. The frame 102 has a window region 112 at a center thereof and a margin region 114 around the window region 112. The straight portions 108 of the lamps 104 are arranged in window region 112 and the connection portions 110 thereof are arranged in the margin region 114.
While the lamps 104 are turned on, the connection portions 110 provide much greater luminance than straight portions 108. That causes the diffuser plate 106 hard to diffuse the light provided from the lamps 11 uniformly. The illuminating unit 100 provides the connection portions 110 of the lamps 104 out of the window region 112, which means, only the straight portions 108 of the lamps 104 provide the light to the diffuser plate 106 and that will make the diffuser plate 106 providing a uniform light to a liquid crystal panel (not shown). The direct-light illuminating unit 100 fixes the problem of the U-shaped lamps hard to be diffused, but it gives a smaller window region and a greater margin region.
In addition, the direct-light illuminating unit 100 has the light generated from the connection portions 110 of the lamps 104 waste, so that it has to provide longer lamps 104 to provide a sufficient luminance.